Drawn-in collet chuck



April 16, 1946. b u 2,398,540

DRAWN-IN COLLET CHUCK Filed Oct. 19. .1945

Patented Apr. 16, 1946' UNITED STATES aramr OFFICE DRAWN-INZCQLLET chuck Joseph-N. Landau, Nature. f Application October 19, 1943, sensin 506,870 l F (crews-53) I l 2 Claims.

This invention relates to chucks and more particularly toimprovements in drawn-in chucks of the collet type for use in connection with the rotatable spindles andarbors of various machines. The chuck or collet forming the subject matter of the present invention is especially adapted for metal working machines wherein it is; desired to provide a more eincient holding device for cylindrical metal stock and metal working tools and thelike.

One important object of the present invention is to provide a novel form of drawn-in chuck which shall be more efl'icient in operation than those now in present day use; P-

Another object of the invention is to provide apparatus of the character designated which shall be more durable in construction andhave a minimum number of moving parts. l

A further object of the invention is to provide apparatus of the character designated which shall be readily adapted to a wider variety of metal working machines than similar devices now in use.

These and other objects of the invention will be more apparent fromthe following specification and drawing and more particularly set forth in the claims.

In the drawing:

Fig. 1 is a longitudinal sectional view of a chuck embodying the features of the present invention;

Fig. 2 is a longitudinal sectional view of a chuck embodying a modification of the apparatus shown in Fig. 1, and

Fig. 3 is a sectional view on line 3-3 of Fig. 2.

Referring to Figs, 1 and 2 of the drawing there is shown a collet chuck embodying the several novel features of the present invention wherein the numeral It] indicates a hollow supporting cylindrlcal body portion of the chuck and II indicates a cooperating hollow cylindrical nose or front body portion. The collet shown in Fig. 1 includes a rearwardly extending tapered body portion l2 which is adaptable for mounting in a rotatable machine socket, not shown, while that illustrated in Fig. 2 includes an interlorly threaded portion I3 for mounting on a threaded machine tool spindle. Whichever form of mounting construction is employed the important feature of the present construction is the particular arrangement for holding and operating the removable collet jaw member indicated by the numeral I4.

The collet jaw member 14 is of the conventional tubular spring jaw type for insertion into the nose portion II. This collet includes forward let member outwardly tapered, sectional spring elements l5-l 5 formed integrally with a rear body portion I6 having an'external'gt hreaded portion IT. The threaded portionfllfljis engaged by a correspondingthreaded portion [8 in: the hollow bore of "The forwarder nose portion of the. device II is provided with an annular rearwardly extendingtubular portion l9 whichis provided with a hollow bore 26 for receiving and mounting the coll4. Theexterior portion of the tubular member I 9 is rotatably mounted within an enlarged annular bore Zl provided in the body member in and the rear end of the member l9 engages a shoulder 22 at the rear thereof by means of a thrust bearing indicated by the numeral 23.

The novel apparatusfor holding and operating the collet jaw member lii includes a pair of segmental holding collar members 2424 shown more clearly in Fig. 3. These collar members are rigidlyfsecured to and form a rigid integral part of the member l9 by meansof an annular groove Z5 and cooperating set screws indicated by the numerals 26-46. A corresponding and complementary groove 21 is cut in the inner periphery of the bore 20 in the member In for receiving the segmental collar members prior to assembly of the parts in their operative positions to form an integral wear collar. The outer periphery of groove 2'! includes a threaded opening 28 for permitting insertion of the set screws 26-46 to securely hold the collar members. This opening is also employed as an internal lubrication opening for permitting lubrication of the interior of the J chuck and is also closed by a threaded plug 29.

The collet member I4 is retained in sliding engagement with the member is by means of a set screw 30 threaded in the member I 9 and having an end projecting into a longitudinally disposed channel 3| formed in the rear outer peripheral surface of the collet body l6.

Located in the interior forward end of the nose portion I! is a rotatable annular bushing 32. This bushing has an annular tapered forward inner portion 33 for frictionally engaging the outer surface of the collet jaws M to force the same radially into engagement with the work being held. This bushing is held in place by means of a set screw 34 having its end projecting with an annular groove 35. The rearward thrust is taken up by an annular disc bearing member 36 engaging a shoulder portion 31 formed in the hollow bore of the rotatable nose section II. An annular hand rim flange 38 is provided on the nose member H for operating the collet as hereinafter described.

reducing friction and strain on the ,partsin the forward and rearward portions of. the chuck, body. This is a considerable advantage in in-- the efficiency of the chuck and facilitates creasing the operation thereof because it provides an enclosed chuck with a minimum number of moving parts which are lubricated in more efficient ma ne Referring to the modification shown in Fig. 2, there is provided a removable interiorly threaded bushing 39 to receive the threaded end of the collet [4. This bushing 39 is rigidly held in place by a set screw Ml threaded into the rear of the body' por'tion l and the bushing. The bushing is' provided at its forward end by a reduced flanged portion sponding flange portion 42 formed on the interior bore of the body I0 and adjacent to the inner end of the rotatable collet holding member l9. This construction provides a removable'bushing longitudinal movement of 4! adapted to engage a correfor receiving different forms or sizes of threaded collets, and is inserted into and removed from the rear of body in by removing the set screw MI. The feature of inserting the bushing from the rear enables the bushing to be removed without dismantling the collet.

To facilitate the removal of the chuck M from the body l0 as shown in Fig. 2, the body In is also provided in the outer periphery with a hole 4 3 which may be of any suitable size or shape to receive a wrench element (not shown).

The chuck embodying the several improvements provides a device which may be adapted for a wide variety of uses and conditions of operation. The two-piece casing elements Ill-ll house the moving parts and provide a more durable apparatus than those heretofore proposed and one which shall have a wide range of adjustability. The particular arrangement and construction of the parts also provides for more efficient lubrication of the several parts.

It will be obvious to those skilled in the art that various changes may be made in my device without departing from the spirit of invention,

therefore I do not limit myself to what is shown in the drawing or described in the specification but only as disclosed in the appended claims. What I claim is:

1. In a device of the character described, a rigid hollow cylindrical chuck having its forward portionenlarged to form a casing member, means at'the'rear of said casing for attaching the same to a support, ,a hand wheel having a hollow hub portion extending rearwardly and rotatably mounted in said rigidcasing member, a collet jaw member located in said casing members, the rear of said collet threadedly engaging a portion of theinterior of the rigid casing for causing the collet relative to the hand wheel and the forward end of the collet frictionally engaging the forward end of the hand wheel hub to effect gripping action of the collet jaws, a circumferential channl formed in the inner periphery of sai d rigid casing member,a

corresponding channel formed on the outer periphery of the rotatable casing member and com-.

plementary .to said first channel member, and a collar member located in said channels for retaining the parts in rotative relation while operating the collet jaw member.

I 2. In' a device of the character described in claim 1, in which the collar member includes a plurality of segments, and means for rigidly securing the segments in thechannel member.

. I l H JOSEPH N. LANDAU. 

